Answer:
2.84 m/s
Explanation:
At the top position of the circular trajectory, the normal reaction is zero:
N = 0
So it means that the only force that is providing the centripetal force is the gravitational force (the weight of the bucket). Therefore we have:
where
m is the mass of the water bucket
g = 9.8 m/s^2 is the acceleration of gravity
v is the speed of the bucket
r = 0.824 m is the radius of the circle
Solving for v,
For rotational equilibrium of the door we can say that torque due to weight of the door must be counter balanced by the torque of external force
here weight will act at mid point of door so its distance is half of the total distance where force is applied
here we know that
now we will have
so our applied force is 72.5 N
Answer:
c)
Explanation:
Coulomb's law says that the force exerted between two charges is inversely proportional to the square of distance between them, and is given by the expression:
where k is a proportionality constant with the value
In this case , so we have:
Solving the equation for q, we have:
Replacing the given values: